Yesterday, the Treasury Department, announcing sanctions on six suspected al Qaeda facilitators, alleged a pact between Iran and al Qaeda. According to a statement, Iran agreed to a “secret deal with al Qaeda allowing it to funnel funds and operatives through its territory.” Treasury offered few details about the deal, leaving its contours mostly a mystery.

“Our sense is this network is operating through Iranian territory with the knowledge and at least the acquiescence of Iranian authorities,” a Treasury official, named in some reports as Undersecretary for Terrorism and Financial Intelligence David Cohen, said in a phone briefing. The Departments of Treasury and State did not respond to requests for interviews.

None of the six people named for sanctions were Iranian, and only one is allegedly based on Iranian soil: Syrian national Ezedin Abdel Aziz Khalil. Of the other named operatives and facilitators, one is based in Iraq, one in Pakistan, one in Qatar and two in Kuwait. The Gulf monarchies of Kuwait and Qatar are close U.S. allies, leading Columbia professor and former Iran-based foreign service officer Gary Sick to comment that articles about the announcement could just as easily have been headlined: “Two U.S. Allies in the Gulf promote and support anti-U.S. terrorism.”

Al Qaeda has long been known to have some affiliated personnel inside Iran. Several operatives fled there after the U.S.-led invasion of Afghanistan in late 2001. But tensions between the Sunni terror group and Iran’s Shia government have long been thought to temper co-operation. Iran detained many of the operatives on its soil, usually at least restricting their travel. Those conditions were reportedly eased when al Qaeda reportedly helped Iran get an agent released by Pakistani militants, according to “Western officials.” Last year, then head of U.S. forces of Afghanistan Gen. David Petraeus said Iran’s attitude toward the group was “unpredictable,” and the Financial Times noted today that “there have been persistent reports of co-operation between the two given that they share a mutual enemy: the U.S.”